Microstructured films, with features on the micrometer scale, have been used in a variety of technologies including overhead projector films, reflective signage, and abrasive films. Common microstructure forming processes include extrusion, embossing, and lithography (e.g., photolithography). Lithographic processes often require complex optics, relatively low throughput, and multiple processing steps, including solution based processing which may generate significant amounts of liquid waste. Microreplication processes such as extrusion and hot embossing typically require expensive master pattern rolls for any given pattern, and any changes to the pattern would require the added expense of a new master to be fabricated. In addition, the patterns are limited in both feature depth and type of pattern (e.g., based on diamond turning methods). In addition, the microreplication processes generally produce materials having a base plane (sometimes referred to as the “land” area) with patterns protruding either all above or all below the base plane. Precise registration of microstructured patterns on opposing sides of a film may allow for simultaneous features both above and below the base plane, however these processes are significantly more complex and often have additional limitations on precision of feature placement above and below the base plane. New patterned microstructured films, and methods of making them, are desirable.